U.S. patent number 5,711,309 [Application Number 08/592,589] was granted by the patent office on 1998-01-27 for apparatus for collecting middle ear specimens.
Invention is credited to Robert A. Goldenberg.
United States Patent |
5,711,309 |
Goldenberg |
January 27, 1998 |
Apparatus for collecting middle ear specimens
Abstract
The present invention is an apparatus and method for collecting
a specimen of middle ear fluid, through the ear drum of a patient,
for subsequent culturing. The present invention involves using a
needle that is adapted for puncturing through the ear drum, with a
fluid absorbent material disposed on the needle to absorb a
sufficient specimen of middle ear fluid for subsequent culturing
and identification of bacteria present. Such an apparatus can be
made inexpensively and disposable after each use. A stop guard can
be secured to the needle to inhibit penetration of the needle
beyond a desired depth through the ear drum. The stop guard enables
the desired depth of penetration, through the ear drum, to be
determined without having to rely solely on the skill of the
practitioner performing the procedure.
Inventors: |
Goldenberg; Robert A. (Dayton,
OH) |
Family
ID: |
26792722 |
Appl.
No.: |
08/592,589 |
Filed: |
January 26, 1996 |
Current U.S.
Class: |
600/583;
606/109 |
Current CPC
Class: |
A61B
10/0045 (20130101); A61B 10/0233 (20130101); A61B
2017/00787 (20130101); A61B 2090/036 (20160201) |
Current International
Class: |
A61B
10/00 (20060101); A61B 19/00 (20060101); A61B
17/00 (20060101); A61B 005/00 () |
Field of
Search: |
;128/760,763,766,765,754
;604/403,410,318 ;606/108,109,167,170,180 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hindenburg; Max
Assistant Examiner: Wingood; Pamela L.
Attorney, Agent or Firm: Killworth, Gottman, Hagan &
Schaeff, L.L.P.
Claims
What is claimed is:
1. An apparatus for collecting a middle ear fluid specimen through
the ear drum of a patient, said apparatus comprising:
a needle having a distal end adapted for puncturing through the ear
drum of a patient; and
a fluid absorbent material disposed on said needle and operatively
adapted to absorb a specimen of middle ear fluid.
2. The apparatus as set forth in claim 1, wherein needle has a
proximal end, and said fluid absorbent material is disposed on the
outside of said needle between said distal end and said proximal
end.
3. The apparatus as set forth in claim 1, further comprising a stop
guard secured to the outside of said needle a desired distance from
said distal end, said stop guard being adapted to inhibit further
penetration of said needle through an ear drum.
4. The apparatus as set forth in claim 1, further comprising a
specimen container having an opening adapted for allowing the
distal end of said needle therethrough and containing a
preservative for preserving a middle ear specimen collected by said
fluid absorbent material.
5. The apparatus as set forth in claim 4, wherein said preservative
is in a package that is puncturable by said needle.
6. The apparatus as set forth in claim 4, wherein specimen
container has a flexible wall and said preservative is in a package
that is breakable by flexing said flexible wall.
7. The apparatus as set forth in claim 1, wherein said needle has a
hollow section with a tubular wall and an opening to said hollow
section, and said fluid absorbent material is disposed at least one
of inside and outside said hollow section.
8. The apparatus as set forth in claim 7, wherein said opening to
said hollow section is formed at said distal end.
9. The apparatus as set forth in claim 7, wherein said opening to
said hollow section is formed through said tubular wall, on the
side of said needle.
10. The apparatus as set forth in claim 7, wherein said needle is a
hollow needle.
11. The apparatus as set forth in claim 10, further comprising an
external vacuum source connected to said hollow needle so as to
draw middle ear fluid into said fluid absorbing material.
12. The apparatus as set forth in claim 1, wherein said needle has
a hollow section with a tubular wall at said distal end, said
tubular wall has at least one perforation formed therethrough and
in fluid communication with an opening to said hollow section at
said distal end, and said fluid absorbent material is disposed on
at least one of the outside of and inside said hollow section
adjacent to said at least one perforation.
13. The apparatus as set forth in claim 12, further comprising a
stop guard secured to said needle a desired distance from said
opening to said hollow section, said stop guard being adapted to
inhibit further penetration of said needle through an ear drum, and
said at least one perforation is disposed between said stop guard
and said opening.
14. The apparatus as set forth in claim 1, wherein said needle
includes a flared portion at said distal end, and said fluid
absorbent material is disposed behind said flared portion.
15. A method for collecting a middle ear fluid specimen through the
ear drum of a patient, said method comprising the steps of:
providing a needle with a distal end adapted for puncturing through
the ear drum of a patient, and a fluid absorbent material disposed
on the needle and operatively adapted to absorb a specimen of
middle ear fluid;
inserting the needle through the ear drum of a patient;
absorbing a specimen of middle ear fluid into the fluid absorbent
material; and
withdrawing the needle from the ear of the patient.
16. The method as set forth in claim 15, further comprising the
step of directing the specimen into a specimen collection container
with a preservative contained therein.
17. The method as set forth in claim 15, further comprising the
step of puncturing a package containing the preservative with the
needle.
18. The method as set forth in claim 15 wherein the needle being
provided has a stop guard secured thereto, and said step of
inserting the needle through the ear drum includes inserting the
needle up to the stop guard.
19. The method as set forth in claim 15, wherein the needle being
provided has a hollow section, with a tubular wall defining an
opening at the distal end, and at least one perforation formed
therethrough, and said step of allowing a specimen of middle ear
fluid to be absorbed includes absorbing a specimen of middle ear
fluid into the fluid absorbent material through the at least one
perforation.
20. The method as set forth in claim 15, wherein the needle being
provided is a hollow needle, and said method further comprises the
step of drawing middle ear fluid into the fluid absorbing material
by connecting the hollow needle to an external vacuum source.
Description
FIELD OF THE INVENTION
The present invention is related to the medical procedure of
removing fluid specimens (e.g., pus and other secretions) from the
middle ear space of a patient, and more particularly to an
apparatus for collecting middle ear specimens through the ear drum
and preserving the specimen for subsequent culturing.
BACKGROUND OF THE INVENTION
Recent medical studies have found that antibiotic resistant
bacterial organisms are becoming more and more prevalent. Most
bacterial infections are cultured and the type of bacteria causing
the infection identified before an antibiotic treatment is
prescribed. Infections of the middle ear (i.e., otitis media) are
one of the few bacterial infections which are routinely treated
without first being cultured and the bacterial strain identified.
In general, without a pre-treatment identification of each
bacterial strain present in the infected area, there is a risk that
the chosen antibiotic treatment will be ineffectual. This risk has
increased with the ever increasing number of antibiotic resistant
bacteria. Depending on the type of infection, prescribing an
ineffectual treatment can unnecessarily prolong a patient's pain
and suffering and may even result in further complications from
recurrent otitis media.
One main reason bacterial ear infections are typically not cultured
and identified before being treated is because the ability to
collect a specimen from the middle ear space has been limited by
the equipment and devices previously used for that purpose. One
such prior collection system had a handle at one end which was
connected to a vacuum pump, a hollow needle at its other end and a
vial attached to the handle for collecting aspirated fluid. The
needle was inserted through a patient's ear drum (i.e., tympanic
membrane) and the vacuum pump was operated to establish a vacuum
used to withdraw fluid from the middle ear space and collect the
fluid in the vial. One problem with this type of collection system
is the need for an external vacuum pump. Such mechanical vacuum
pumps are expensive and not always available when and where needed,
for example, in many less developed countries and under served
areas of even major industrialized countries. Because some type of
tubing and connector is needed to connect the specimen aspirator to
the external vacuum pump, this type of collection system can be
cumbersome and unwieldy, making it difficult to collect a specimen
of middle ear fluid.
A collection apparatus which does not require an external vacuum
source is disclosed in U.S. Pat. No. 4,641,663. This collector is a
hypodermic needle assembly with a plunger which is spring loaded to
draw fluid through its hollow needle once a latch mechanism is
released. While it is self-contained (i.e., does not use an
external suction pump or vacuum source) and disposable, this
specimen aspirator is still relatively complex and, thus, expensive
to manufacture. A problem shared by both of the above described
prior specimen collection systems is that the depth of penetration
by the hollow needle, into the middle ear space, is largely
dependent on the skill and experience of the person performing the
procedure. Thus, the use of either of these devices is likely to be
limited to only the most experienced practitioners.
Therefore, especially with the apparent continued proliferation of
antibiotic resistant bacteria, there is an increasing need for a
disposable and inexpensive apparatus for collecting a fluid
specimen from the middle ear space of a patient without the need of
an external vacuum source (i.e., self-contained). There is a
further need for such an apparatus which does not rely solely on
the practitioner's skill to determine the depth of penetration
through the ear drum.
SUMMARY OF THE INVENTION
These needs are met by providing an apparatus and method, according
to the principles of the present invention, for collecting a middle
ear fluid specimen through the ear drum of a patient. Broadly, the
present invention involves using a needle that is adapted for
puncturing the ear drum. A fluid absorbent material is secured to
the needle so as to absorb a specimen of middle ear fluid, when
disposed through the ear drum. Such an apparatus can be made
inexpensively and disposable after each use. The present invention
eliminates the need of using relatively complex structure for
producing a vacuum, such as an external vacuum source, to obtain a
specimen of middle ear fluid.
In one aspect of the present invention, an apparatus is provided
which comprises such a needle and fluid absorbent material. One
possible feature of the present apparatus is a stop guard that is
secured to the outside of the needle. The stop guard is adapted to
inhibit penetration of the needle beyond a desired depth through an
ear drum. That is, once the desired depth through the ear drum is
reached, the stop guard provides enough resistance to further
penetration that a practitioner can tell that the desired depth has
been reached. Thus, with this feature, the depth of penetration
through the ear drum can be determined without having to rely
solely on the skill of the practitioner performing the
procedure.
It may be desirable for the collected middle ear specimen to be
kept in a specimen collection container. The specimen collection
container can be any structure suitable for keeping the collected
specimen in condition for subsequent culturing and identification
(e.g., a test tube, a sheath suitable for receiving and being
secured to the needle, etc.). It may be desirable for the specimen
collection container to include a preservative (i.e., any suitable
medium for keeping bacteria in the specimen viable for subsequent
culturing and identification). The preservative can be simply
deposited within the specimen container or separately packaged
therewithin. For example, the preservative can be disposed in a
package that is puncturable by the needle. Alternatively, the
specimen container can be formed with a flexible wall, and the
preservative can be disposed in a package that is breakable by
flexing the flexible wall.
The fluid absorbent material can be disposed on the outside of the
needle between its distal and proximal ends. Alternatively, when
the needle has a hollow section with a tubular wall and an opening
leading to the hollow section, the fluid absorbent material can be
disposed inside the hollow section. The opening to the hollow
section can be formed at the distal end of the needle or through
the wall of the hollow section on the side of the needle. For ease
of manufacturing, when the needle includes such a hollow section,
the length of the needle can be made hollow. It may be desirable
for such a hollow needle to be connectable to an external suction
or vacuum source (e.g., an external vacuum pump) in order to draw
middle ear fluid into the fluid absorbent material. The costly
external vacuum source can be reused while the relatively
inexpensive needle of such an apparatus can be disposable.
A middle ear specimen can also be collected for culturing and
identification, according to the present invention, by making the
needle at least partially hollow at its distal end and forming one
or more perforations through its tubular wall, with the one or more
perforations being in fluid communication with the opening leading
to the hollow section. With such an embodiment, the fluid absorbent
material is either disposed on the outside or on the inside of the
hollow section adjacent to the perforations so as to absorb at
least part of a fluid specimen through one or more such
perforations. When the needle includes a stop guard, it is
desirable for the one or more perforations to be disposed between
the stop guard and distal end of the needle.
The needle can include a flared portion at its distal end to
protect the fluid absorbent material from having portions of the
absorbing material dislodged while the distal end of the needle is
forced through and removed from an ear drum. This portion is flared
so as to be generally flush with or extend radially out beyond the
outer surface of the absorbent material. The fluid absorbent
material is disposed behind the flared portion of the needle.
In another aspect of the present invention, a method is provided
comprising the steps of: providing a needle as described above;
inserting the needle through the ear drum of a patient; absorbing a
specimen of middle ear fluid into the fluid absorbent material; and
withdrawing the needle from the ear of the patient. The present
method can further comprise the step of directing the specimen into
a specimen collection container with a preservative contained
therein. The present method can also further comprise the step of
puncturing a package containing the preservative, with the needle.
With the above described stop guard being secured to the needle,
the step of inserting the needle through the ear drum includes
inserting the needle up to the stop guard. With the needle having
at least one perforation as described above, the step of allowing a
specimen of middle ear fluid to be absorbed includes absorbing a
specimen of middle ear fluid into the fluid absorbent material
through one or more such perforations.
The objectives, features, and advantages of the present invention
are apparent upon consideration of the present specification and
the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially broken-away sectional view of one embodiment
of the present apparatus for collecting a middle ear fluid specimen
through the ear drum of a patient, including a specimen collection
container;
FIG. 2 is a side view of another embodiment of the present
apparatus in position to collect a fluid specimen, with the ear of
a patient shown in cross-section;
FIG. 3 is an enlarged side view of one embodiment of a distal end
of a needle used to form part of an apparatus of the present
invention;
FIG. 4 is an enlarged sectional view of another embodiment of a
distal end of a needle used to form part of an apparatus of the
present invention; and
FIG. 5 is an enlarged sectional view of an additional embodiment of
a distal end of a needle used to form part of an apparatus of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
Although the present invention is herein described in terms of
specific embodiments, it will be readily apparent to those skilled
in this art that various modifications, re-arrangements, and
substitutions can be made without departing from the spirit of the
invention. The scope of the present invention is thus only limited
by the claims appended hereto.
An apparatus 10, according to the present invention, broadly
includes a needle 12 mounted on a handle 14. The needle 12 has a
distal end 16 with a pointed tip 17, for puncturing through the ear
drum 18 of a patient (see FIG. 2). The needle 12 can be straight or
formed with a desired bend (see FIGS. 1 and 2, respectively) and is
sufficiently long to reach and penetrate the ear drum 18. A fluid
absorbent material 20 is secured to the needle 12 so as to absorb a
specimen of middle ear fluid 22, when disposed through the ear drum
18. The fluid absorbent material 20 may include, for example, one
or a combination of cotton, cotton-wool and calcium alginate, to
name a few.
Referring to FIG. 1, in one embodiment of apparatus 10, generally
designated by the reference numeral 24, the needle 12 is straight
and the handle 14 includes a hub 26 that mounts the proximal end of
the needle 12. The hub 26 can be an integral part of the handle 14
(as shown) or removably mounted to the handle 14. The hub 26 is
adapted to be secured to a specimen container 28 used to store the
specimen of middle ear fluid 22, collected by the absorbent
material 20, for subsequent culturing.
The specimen container 28, for example, can be in the form of a
sheath, similar to those used to protect conventional hypodermic
needles. The sheath 28 has an opening 30 leading to a containment
chamber 32. The specimen of fluid 22 is stored in the container 28
by disposing the needle 12 through the opening 30 and into chamber
32. The sheath 28 can be adapted to receive the full length of the
needle 12 and so that the hub 26 seats inside the opening 30, for
example, with an interference or press fit. It is desirable to keep
the opening 30 of the specimen container 28 closed until the
specimen can be cultured, to prevent the specimen from being
inadvertently lost or contaminated. Therefore, it may be desirable
for the hub 26 and the container 28 to be connected to one another
more securely than by using an interference or press fit, to insure
that a sterile non-contaminated environment is maintained around
the specimen of middle ear fluid 22. A threaded connection, a
luer-lock connection or any other more secure connecting system can
be used to removably connect together the hub 26 and the container
28. For example, the mating surfaces 34 and 36 of the container
opening 30 and the hub 26, respectively, can be formed with threads
and threadably engaged, rather than press fit together.
It may be desirable to use a preservative 38 which is suitable for
preserving the specimen of middle ear fluid 22 in condition for
subsequent culturing and identification. The preservative 38 may
be, for example, a liquid such as distilled water, saline solution,
or other non-reactive liquid which will provide an environment in
which the bacteria will remain viable for subsequent culturing. The
preservative 38 may also be one or a combination of Stuart's
Medium, Bartel's Biotransport Medium and thioglycollate. The
preservative 38 can be unconstrained and free to move about within
the chamber 32. However, to prevent the likelihood of spillage, it
is desirable for the preservative 38 to be kept constrained within
a separate package 40, such as the frangible ampoule disclosed in
U.S. Pat. No. 3,450,129, which is incorporated herein by reference
in its entirety. When the preservative 38 is kept in such a
frangible ampoule 40, it is desirable for the wall of the container
28 to be collapsible in order to fracture the ampoule 40 and
release the liquid preservative 38. The package 40 containing the
preservative 38 can also be made puncturable, by the pointed tip 17
of the needle 12, to effect the release of the preservative 38.
It is desirable for a stop guard 42 to be mounted or otherwise
disposed on the needle 12 to inhibit penetration of the needle 12
beyond a desired depth through the ear drum 18 (see FIG. 2). That
is, once the desired depth through the ear drum 18 is reached, the
stop guard 42 provides enough resistance to further penetration
that a practitioner handling the apparatus 10 can tell that the
desired depth has been reached. Thus, the depth of penetration
through the ear drum 18 can be determined without having to rely
solely on the skill of the practitioner performing the
procedure.
It is believed that a number of suitable designs for the stop guard
42 are feasible. For example, the stop guard 42 can be a ring
formed around the outside of the needle 12. The ring shaped stop
guard 42 can be bell shaped (see FIGS. 1, 2 and 5), washer-shaped
(see FIG. 3), cone-shaped (see FIG. 4) or any other suitable
configuration. It is desirable for the stop guard 42 to be bonded
or otherwise fixed at a desired location on the needle 12. To this
end, the stop guard 42 can be manufactured as an integral part of
the needle 12. For example, the stop guard 42 can be formed along
with the needle 12, such as when both are molded using a plastic
material. The stop guard 42 can also be welded in place to the
needle 12, such as when they are both made of a metal.
Alternatively, it may be desirable to make the location of the stop
guard 42, on the needle 12, adjustable. This adjustability can be
obtained by making the stop guard 42 with an inside diameter that
forms an interference or press fit when slipped over the needle 12.
Such a stop guard 42 can be made adjustable and still sufficiently
inhibit further penetration of the needle 12 through the ear drum
18 by adjusting the strength of the interference or press fit
(i.e., varying the inside diameter of and/or the material used to
make the stop guard 42).
The fluid absorbent material 20 can be, for example, in the form of
fibers 44 wrapped around the distal end 16 of the needle 12 (see
FIG. 3). The material 20 can also be in the form of a fibrous mat
46 disposed inside or outside the distal end 16 of the needle 12
(see FIGS. 4 and 5, respectively). It is understood that the
present invention is not intended to be so limited. The fluid
absorbent material 20 can include any suitable material and have
any suitable form for absorbing middle ear fluid. It is important
that the fluid absorbent material 20 be able to not only absorb a
sufficient amount of middle ear fluid 22 but also enable any
bacteria present in the absorbed specimen to be subsequently
cultured and identified.
Referring to FIG. 3, the needle 12 of an apparatus 10 can have a
uniform cross-section up to its pointed tip 17. With the pointed
tip 17 being conically-shaped (as shown), it may be desirable for
its fluid absorbing material 20 to be disposed on the outside of
the distal end 16 with at least a leading portion 48 tapered so as
to form a gradual transition between the pointed tip 17 and the
material 20.
In addition, referring to FIG. 4, the needle 12 of an apparatus 10
can have a hollow section 50 formed by a wall 51 and an access
opening 52 leading to the hollow section 50. The mat 46 of fluid
absorbent material 20 is disposed inside the hollow section 50
through the opening 52. The opening 52 provides a path through
which middle ear fluid 22 can reach and be absorbed by the fluid
absorbing material 20. For ease of manufacturing, the hollow
section 50 can be formed by making the length of the needle 12
hollow (indicated with phantom lines 54). Accordingly, the opening
52 leading to the hollow section 50 can be formed through the wall
51 on the side of the needle 12 (as shown) and/or through its tip
17 (as shown in phantom). It may be desirable for the hollow needle
12 to be operatively adapted so as to be connectable to external
suction or vacuum source, such as a conventional medical vacuum
pump, in order to draw middle ear fluid into the fluid absorbent
material.
Furthermore, referring to FIG. 5, the pointed tip 17 of the needle
12 of an apparatus 10 can include a flared portion 56 to protect
the fluid absorbent material 20 from having portions of the
absorbing material 20 dislodged while the distal end 16 of the
needle 12 is forced through and removed from an ear drum 18. The
fluid absorbent material 20 is disposed behind the flared portion
56 of the needle 12, and this portion 56 is flared so as to be
generally flush with or extend radially out beyond the outer
surface of the absorbent material 20. Thus, whenever the fluid
absorbent material 20 is disposed on the outside of the needle, it
may be desirable for the tip 17 of the needle 12 to include a
flared portion 56, regardless of whether the needle is hollow (like
that shown in FIG. 5) or solid (like that shown in FIG. 3).
Also referring to FIG. 5, the needle 12 of an apparatus 10 can have
a hollow section 57 formed along at least part of its distal end 16
(e.g., by using a hypodermic needle for the needle 12), with a
tubular wall 58 and one or more perforations 60 formed through its
tubular wall 58. The perforations 60 are in fluid communication
with an opening 62 formed through the tip 17. The fluid absorbent
material 20 can be disposed on the outside (as shown) of the
tubular wall 58 adjacent to the perforations 60. When the absorbing
material 20 is so disposed on the outside of the perforated tubular
wall 58, more surface area of the absorbing material 20 is
available for absorbing middle ear fluid 22. The underside of the
material 20 can absorb middle ear fluid 22 present in the hollow
section 57 through one or more of the perforations 60, and the
outer surface of the material 20 can absorb fluid 22 it comes in
direct contact with. By increasing the surface area of material 20
exposed to fluid 22, the amount of fluid 22 collected by the
absorbent material 20 can also be increased. When the needle 12
includes a stop guard 42, the perforations 60 are disposed on the
distal end 16 of the needle 12, in front of the stop guard 42. It
may also be desirable, with this embodiment, to draw middle ear
fluid 22 into the hollow section 57 using an external vacuum or
suction source, such as a conventional medical vacuum pump,
connected to the proximal end of the hollow needle 12.
Referring to FIG. 2, during the collection of a specimen of middle
ear fluid 22 according to the present invention, it is desirable to
use a conventional otoscope 64 with any embodiment of apparatus 10.
In one method for collecting a specimen of middle ear fluid 22, the
otoscope 64 is inserted into the patient's ear and used to locate
the ear drum 18. The needle 12 is then inserted through the
otoscope 64 and the distal end 20 is forced through the ear drum 18
until the stop guard 42 makes contact with the ear drum 18. To help
ensure that the fluid absorbent material 20 contacts and absorbs a
sufficient amount of middle ear fluid 22, it may be desirable to
rotate the needle 12 slightly, about its longitudinal axis. The
needle 12 is then withdrawn from the patient's ear. The distal end
20 of the needle 12 can then be inserted into a specimen container
28 through its opening 30, and the opening 30 is then closed, for
example, as described above. The preservative 38 is then freed from
its package 40, as describe above, and allowed to saturate the
absorbent material 20. The collected specimen of middle ear fluid
22 is now ready for subsequent culturing to identify the bacteria
present in the patient's middle ear, using conventional culturing
and identification techniques.
From the above disclosure of the general principles of the present
invention and the preceding detailed description, those skilled in
this art will readily comprehend the various modifications to which
the present invention is susceptible. Therefore, the scope of the
invention should be limited only by the following claims and
equivalents thereof.
* * * * *